140mm f/7.5 Starfire EDF - 5.5" aperture:
with 2.7" Focuser
with 4" Focuser (140EDF4)

The 140mm f/7.5 StarFire EDF is not available to purchase and we do not have any plans to produce additional scopes with these exact specifications. This information is presented for present owners and those who are curious about its history.

Roland Christen at NEAF with the 140mm f/7.5 StarFire EDF and 900GTO German Equatorial Mount.

Astro-Physics introduced the prototype of this new triplet apochromatic refractor at the Northeast Astronomy Forum (NEAF) on April 28, 2007. Roland designed this scope with approximately the same focal length as our original 155mm f/7 StarFire (as well as the 130 f/8 and f/8.3 StarFires), so that it can be used with all of the same specialized astrophotography / imaging accessories that were originally designed for these earlier telescopes. Visual astronomers will enjoy the 1050mm focal length, which allows a full range of eyepiece designs from simple to complex to produce extremely sharp planetary images. We are certain that astro-imagers, as well as visual observers, will find this scope a real joy to use.

Lens: This new triplet refractor features exquisite Astro-Physics optics and has the latest multi-coating technology, just like our 160mm StarFire EDF. This oil-spaced apochromat uses the highest grade of optical glass to achieve exceptional image brightness and excellent color correction, ideal for all visual and imaging needs.

Tube assembly: As with all Astro-Physics refractors, tube assembly construction is robust, yet light-weight for its size. Multiple machined-in baffles reduce stray light to a minimum. The lens resides in a push-pull cell that maintains its collimation even under conditions of vibration during shipping. The new sliding dewcap has a built-in baffle to help prevent dew as well as block stray light. The rotating focuser collar will enable you to frame your images for optimal, artistic composition.

Focuser: The 140EDF will be offered with your choice of Astro-Physics 2.7" 27FOC3E-FT or 4" Giant 4FOC3E-FT) greaseless focusers. Both focusers feature the FeatherTouch 9:1 dual-speed reduction knobs. Full details are available at the links above. Focus travel is a generous 112mm (4.4") for the 2.7" focuser and 107mm (4.2") for the 4" focuser. The focusers are positioned so that the Baader Planetarium Mark V Binocular Viewer will come to focus without the 1.25x compensator. This allows the user to see glorious wide-field views with both eyes - a real treat.

The Giant 4" focuser will allow you to enjoy any and all of your astronomy pursuits. The 4" ID of the drawtube will allow maximum coverage of the Pentax 6 x 7 cm negative for medium format photography. The inside of the drawtube has a series of knife-edge baffles for maximum contrast. Choose from a full line of photographic accessories for CCD imaging, 35mm, digital and medium format film photography. These include the 4" Prime Focus Field Flattener (S155EDFFF) and the new, dedicated 0.76x CCD Telecompressor Corrector (155TCC). With the 4" field flattener, it will cover a 100mm circle at f7.8, and with the 155TCC, it will cover approximately a 57mm circle at f5.7. All of the accessories listed for the 2.7" focuser below can be used with the 4" focuser as well, by using the 4" to 2.7" reducer that is included.

You may want to order your scope with a 2.7" focuser if you are a visual observer or you do not plan to use the 4" Field Flattener or CCD Telecompressor Corrector described above. You will still have ample options for CCD imaging and photography. For instance, you can consider the 2.7" Prime Focus Field Flattener (67PF582), the general purpose 0.75x Photo-Visual Telecompressor (27TVPH) and also the CCD Telecompressor (CCDT67). As an added benefit, your 140 refractor will be 3 lbs lighter with the 2.7" focuser. Also, bear in mind that you can always upgrade to the Giant 4" Focuser at a later time with relative ease if your needs change.

M-17, Imaged with an
AP 140 F7.5 Starfire at F/5.7
NGC 6888, Imaged with an
AP 140 F7.5 Starfire at F/5.7

M-17 taken with an AP 140mm F/7.5 Starfire EDF refractor working at F/5.7 with the 155TCC Telecompressor Corrector. STL11000 camera,
2 x 20 minutes H-alpha and 2 x 20 minute O3.
Red = Ha, green = 1/2(Ha + O3), blue = O3 .
Image by Roland Christen.
Larger version of M17
Cropped close-up image at full resolution.

NGC 6888 taken with an AP 140 F/7.5 Starfire refractor working at F/5.7 with the 155TCC Telecompressor Corrector. STL11000 camera, 10nm Ha filter, 4 hours.
Image by Roland Christen.
Larger Ha version of NGC 6888
Color version of NGC 6888.
Cropped close-up of color image.

Suggested Mountings: The Mach1GTO, 900GTO or 1200GTO German Equatorial mounts are all recommended for astrophotography, depending on your requirements for portability and the amount of wind you are likely to encounter at your photographic site. They are, of course, all three a delight for GoTo visual observing!

Color correction Less than + - 0.004% focus variation from 656nm to 430nm (c to g wavelengths). Color Correction Curve and other Data
Clear aperture 140mm (5.5")
Focal length 1050mm (41.4")
Photographic speed f/7.5
Theoretical Resolution 0.8 arc seconds
Coatings Multi-layer, broadband, overall transmission greater than 97% in peak visual wavelengths
Magnification range 18x to 550x
Tube assembly White, 6.5" aluminum tube, baffled, flat black interior, push-pull lens cell, engraved retaining ring
Focuser choices 2.7" 27FOC3E-FT or 4" 4FOC3E-FT Focusers with rotating collar, rack and pinion with FeatherTouch Micro 9:1dual-speed reduction, 2" and 1.25" adapters.
The 4" Focuser also includes a 4" to 2.7" adapter (A1024) and large Extension (4FOCEXT).
The 2.7" Focuser includes our thread-in extension (A1008-A).
Telescope length 940mm (37") w/ dewcap fully retracted
Diameter of Dewcap 184mm (7.25") OD including paint thickness
Weight with dewcap 24 lbs. (11 kg) with 2.7" focuser
27 lbs. (12.3 kg) with 4" focuser
Carrying-case type Wood case with grey vinyl covering and foam-lined interior

Photographic Field
35mm Photographic field at prime-focus 1.25 x 1.8 degrees @ f7.5
35mm Photographic field with 2.7" telecompressor (27TVPH) 1.7 x 2.5 degrees @ f5.7
35mm Photographic field with 2x Barlow 0.63 x 0.9 degrees @ f15


We have prepared some pertinent support documents relating to this scope and many of our other products on our Technical Support page. Please check there first to find the information that you need.

Upgrades and Spare Parts

Check out our website to find accessories, replacement parts or learn about possible upgrades for your scope.

Copyright 2004-2019 Astro-Physics Inc. All rights reserved.
Last modified: March 11, 2019

Astro-Physics, Inc.
11250 Forest Hills Road, Machesney Park, IL  61115, U.S.A.
Phone: 815-282-1513   Fax: 815-282-9847